site-creation-rest.md: add link to Invoke-PnPSPRestMethod.

Author: fowl2

docs/apis/site-creation-rest.md

@@ -23,6 +23,11 @@ The following REST commands are available for creating a modern SharePoint Commu
 
 The base URL for the REST commands is `_api/SPSiteManager`.
 
+> [!INFORMATION]
+> From PowerShell you can use [Invoke-PnPSPRestMethod](/powershell/module/sharepoint-pnp/invoke-pnpsprestmethod) to call these methods.
+
+[!INCLUDE [pnp-powershell](../../includes/snippets/open-source/pnp-powershell.md)]
+
 ## Create a modern site
 
 Using the following REST API you can create both Communication sites and Non-group associated Team Sites.